/*
 * Copyright 2009-2011 Cedric Priscal
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <termios.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
#include <jni.h>

#include "SerialPort.h"

#include "android/log.h"
#include <jni.h>

static const char *TAG = "serial_port";
#define LOGI(fmt, args...) __android_log_print(ANDROID_LOG_INFO,  TAG, fmt, ##args)
#define LOGD(fmt, args...) __android_log_print(ANDROID_LOG_DEBUG, TAG, fmt, ##args)
#define LOGE(fmt, args...) __android_log_print(ANDROID_LOG_ERROR, TAG, fmt, ##args)

static speed_t getBaudrate(jint baudrate) {
	switch(baudrate) {
		case 0: return B0;
		case 50: return B50;
		case 75: return B75;
		case 110: return B110;
		case 134: return B134;
		case 150: return B150;
		case 200: return B200;
		case 300: return B300;
		case 600: return B600;
		case 1200: return B1200;
		case 1800: return B1800;
		case 2400: return B2400;
		case 4800: return B4800;
		case 9600: return B9600;
		case 19200: return B19200;
		case 38400: return B38400;
		case 57600: return B57600;
		case 115200: return B115200;
		case 230400: return B230400;
		case 460800: return B460800;
		case 500000: return B500000;
		case 576000: return B576000;
		case 921600: return B921600;
		case 1000000: return B1000000;
		case 1152000: return B1152000;
		case 1500000: return B1500000;
		case 2000000: return B2000000;
		case 2500000: return B2500000;
		case 3000000: return B3000000;
		case 3500000: return B3500000;
		case 4000000: return B4000000;
		default: return -1;
	}
}

static int getDataBits(jint dataBits) {
	switch(dataBits) {
		case 5: return CS5;
		case 6: return CS6;
		case 7: return CS7;
		case 8: return CS8;
		default: return -1;
	}
}

static int getStopBits(jint stopBits) {
	switch(stopBits) {
		case 1: return 0;
		case 2: return CSTOPB;
		default: return -1;
	}
}

static int getParity(jint parity) {
	switch(parity) {
		case 0: return 0; // 无校验
		case 1: return PARENB | PARODD; // 奇校验
		case 2: return PARENB; // 偶校验
		default: return -1;
	}
}

/*
 * Class:     com_yx_serialport_SerialPort
 * Method:    open
 * Signature: (Ljava/lang/String;IIIII)Ljava/io/FileDescriptor;
 */
JNIEXPORT jobject JNICALL
Java_com_yx_serialport_SerialPort_open(JNIEnv *env, jclass clazz, jstring path,
									   jint baudrate, jint dataBits, jint stopBits,
									   jint parity, jint flags) {
	int fd;
	speed_t speed;
	jobject mFileDescriptor;
	int dataBitsValue, stopBitsValue, parityValue;

	/* 检查参数 */
	speed = getBaudrate(baudrate);
	dataBitsValue = getDataBits(dataBits);
	stopBitsValue = getStopBits(stopBits);
	parityValue = getParity(parity);

	if (speed == -1) {
		LOGE("Invalid baudrate: %d", baudrate);
		return NULL;
	}

	if (dataBitsValue == -1) {
		LOGE("Invalid data bits: %d", dataBits);
		return NULL;
	}

	if (stopBitsValue == -1) {
		LOGE("Invalid stop bits: %d", stopBits);
		return NULL;
	}

	if (parityValue == -1) {
		LOGE("Invalid parity: %d", parity);
		return NULL;
	}

	/* 打开设备 */
	{
		jboolean iscopy;
		const char *path_utf = (*env)->GetStringUTFChars(env, path, &iscopy);
		LOGD("Opening serial port %s with flags 0x%x", path_utf, O_RDWR | flags);
		fd = open(path_utf, O_RDWR | flags);
		LOGD("open() fd = %d", fd);
		(*env)->ReleaseStringUTFChars(env, path, path_utf);
		if (fd == -1) {
			LOGE("Cannot open port: %s", path_utf);
			return NULL;
		}
	}

	/* 配置设备 */
	// 修改SerialPort.c中的串口配置部分
/* 配置设备 */
	{
		struct termios cfg;
		LOGD("Configuring serial port");
		if (tcgetattr(fd, &cfg)) {
			LOGE("tcgetattr() failed");
			close(fd);
			return NULL;
		}

		// 清空配置
		cfmakeraw(&cfg);

		// 设置输入输出波特率
		cfsetispeed(&cfg, speed);
		cfsetospeed(&cfg, speed);

		// 设置数据位
		cfg.c_cflag &= ~CSIZE;
		cfg.c_cflag |= dataBitsValue;

		// 设置停止位
		if (stopBitsValue == CSTOPB) {
			cfg.c_cflag |= CSTOPB;
		} else {
			cfg.c_cflag &= ~CSTOPB;
		}

		// 设置校验位
		if (parityValue != 0) {
			cfg.c_cflag |= parityValue;
			cfg.c_cflag |= INPCK; // 启用输入奇偶校验
		} else {
			cfg.c_cflag &= ~PARENB;
		}

		// 其他重要设置
		cfg.c_cflag |= (CLOCAL | CREAD); // 本地连接，启用接收
		cfg.c_cflag &= ~CRTSCTS; // 禁用硬件流控制
		cfg.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); // 原始模式
		cfg.c_oflag &= ~OPOST; // 原始输出
		cfg.c_cc[VTIME] = 0; // 读取超时（单位：0.1秒）
		cfg.c_cc[VMIN] = 1; // 读取最小字节数

		// 清空输入输出缓冲区
		tcflush(fd, TCIOFLUSH);

		if (tcsetattr(fd, TCSANOW, &cfg)) {
			LOGE("tcsetattr() failed");
			close(fd);
			return NULL;
		}
	}

	/* 创建对应的文件描述符 */
	{
		jclass cFileDescriptor = (*env)->FindClass(env, "java/io/FileDescriptor");
		jmethodID iFileDescriptor = (*env)->GetMethodID(env, cFileDescriptor, "<init>", "()V");
		jfieldID descriptorID = (*env)->GetFieldID(env, cFileDescriptor, "descriptor", "I");
		mFileDescriptor = (*env)->NewObject(env, cFileDescriptor, iFileDescriptor);
		(*env)->SetIntField(env, mFileDescriptor, descriptorID, (jint)fd);
	}

	return mFileDescriptor;
}

/*
 * Class:     com_yx_serialport_SerialPort
 * Method:    close
 * Signature: ()V
 */
JNIEXPORT void JNICALL
Java_com_yx_serialport_SerialPort_close(JNIEnv *env, jobject thiz) {
jclass SerialPortClass = (*env)->GetObjectClass(env, thiz);
jclass FileDescriptorClass = (*env)->FindClass(env, "java/io/FileDescriptor");

jfieldID mFdID = (*env)->GetFieldID(env, SerialPortClass, "mFd", "Ljava/io/FileDescriptor;");
jfieldID descriptorID = (*env)->GetFieldID(env, FileDescriptorClass, "descriptor", "I");

jobject mFd = (*env)->GetObjectField(env, thiz, mFdID);
jint descriptor = (*env)->GetIntField(env, mFd, descriptorID);

LOGD("close(fd = %d)", descriptor);
close(descriptor);
}